Sharp Aquos LC-32AD5E-BK wont come on

[bbjunkie]

Was out today at a friends, and he gave me a TV to look at for him

This one is a Sharp Aquos LC-32AD5E-BK - a 32" LCD with dvb-t and analogue tuner.

Brought it home and plugged it in, after 5 seconds or so there's a click from the PSU and the green LED lights on the front panel.

There is no response from the remote, or any buttons on the TV at all.

Will be taking the back off later and will post pics then.

Jim

[selldoor]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Here is the schematic

http://www.eserviceinfo.com/download...32AD5E-BK.html

upload failed

[tom66]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Well, the obvious check is the supply voltages and look out for bad caps.

I recall some Sharp TVs may have been made by Vestel at one time or another, but I might be getting confused with Sanyo.

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Thanks for the link selldoor

Ok, back off.. very impressed with the psu board, definitley not Vestel. All caps are Rubycon.

All voltages present apart from 12v at connector CP411 pins 8 and 9 which are reading 0.7vdc

Checked a few 16v caps 470uf and 1000uf and all are reading 0.00 esr - a 220uf 16v cap (C459)is reading 190uf 0.4 ohms though

This is high, right? Will go looking in the junk pile for something suitable (purely to test)

Am unable to get good pics, will try tomorrow in daylight.

Jim

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Found a Rubycon 220uf 35v with esr of 0.2 so put that in, no difference.

Am I right in thinking there should be 12VDC WRT Ground at pins 8 and 9 of CP411 (SW+12V) ? I have tried measuring it while operating the on/off switch also. No difference, still 0.7v dc

Pic attached, best I can do until tomorrow.

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

D440 is reading funny, will remove from circuit and check

<edit> checked out ok, refitted. Checked voltage at pin2 of D440 showing 14VDC

C435 checks good at 980uf 0.00 ohms ESR, R521 isn't shorted cant find R467 but if I'm reading the schematic right if it was shorted I wouldnt be getting a voltage at D440 Pin2 anyway.

The only thing left is wire link W809 which i'm having difficulty finding on the board!

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

I've found a problem.. F404 is a 1.6A micro fuse, between W809 and pin8 and 9 of CP411. It reads open circuit. It would have been much easier to find if it had been shown on the psu schematic!

Perhaps something on the main board caused it go blow?

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Sure enough, resistance between ground and where pin9 of CP411 enters CP3801 is dead short.

Think i've done enough for tonight, time for some dinner!

<edit> miscounted the pins - much more difficult to count with the psu disconnected.

Turns out no short, shows varying resistance around 5K Ohms I guess due to capacitance.

So, V/R 12/5000 = 0.0024 amps, I should be safe enough to replace the fuse?

[tom66]

Re: Sharp Aquos LC-32AD5E-BK wont come on

[edit, too late posting.]

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

I'm having trouble finding the correct Sharp part, so am going to fit an equivalent.

Is this likely to be a fast or slow blow fuse?

Part number is 9JD0835C01603 / 20N_1600FS

[popeye]

Re: Sharp Aquos LC-32AD5E-BK wont come on

the part is shown on the circuit diagram it is a 1.6A 125V fast blow it is in the switched 12v supply line-part number 20N-1600FS check your usual parts supplier it is not just a sharp part. get more than one if it blows straight away then you will have to start checking componants in that area just post again if you need any more help there are plenty of engineers on here that will help you.

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Lots of suppliers have 1.5A and 2A but only one has a 1.6A listed and they are talking a 2 week lead time.

(This is an axial fuse soldered on the board, not a 20mm glass one)

[tom66]

Re: Sharp Aquos LC-32AD5E-BK wont come on

I would go for 2A. No harm in increasing a fuse like that a little bit. (If there's a short circuit, it will blow very quickly.)

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Fitted a 2A axial fuse this evening. Set now powers up and have sound but there is no picture. Backlight is on, first couple of times I powered it up it was showing coloured lines flashing around the screen both vertical and horizontal disco style along with a funky little noise which was in time with the lines changing from the top area probably around the tcon.

Now when I power it up I just get a line, or band in a random place usually horizontally across the screen that quickly disappears to leave just a black screen with backlight on.

Have tried reseating the LVDS cable at both ends

Does this sound like a tcon fault?

[retiredcaps]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Does this sound like a tcon fault?

Post a picture of it.

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Forgot to say in my last post that I couldnt get it to do the whole coloured lines thing again but would try later after it had sat for a while turned off.

Well, turned it on after about an hour and caught a good video of it happening, this can be seen at http://www.youtube.com/watch?v=ZafYbp6L4eo

A photo can't really articulate the fault due to the speed of change of the display.

Hope this is suitable.

[retiredcaps]

Re: Sharp Aquos LC-32AD5E-BK wont come on

A photo can't really articulate the fault due to the speed of change of the display.

Sorry, I meant a picture of the t-con.

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Here we go

[bbjunkie]

Re: Sharp Aquos LC-32AD5E-BK wont come on

Am considering pulling the tcon and checking SMD caps before ordering a new board.

Has anyone seen this issue before (on any make or model)?

Don't want to throw money at a board if it's not going to fix it, as it's for a friend I have nothing much to gain and the cost of a board to loose if it doesn't fix it.

[tom66]

Re: Sharp Aquos LC-32AD5E-BK wont come on

I would check if there are any waveforms appearing at the LVDS connections.